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Share based compensation arrangement by share based payment award equity instruments other than options dividend reinvestment.

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Share-based compensation arrangement by share-based payment award maximum amount increased per employee.

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Share based compensation arrangement by share based payment award maximum amount per employee.

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Percentage of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options awarded under the plan during the reporting period.

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Share based compensation arrangement by share based payment award vesting period description.

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Share based compensation arrangement minimum period of service.

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Stock exercise price as percentage of closing market price.

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Number of shares of equity interests issued or issuable to acquire entity.

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Aggregate number of common shares reserved for future issuance.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Percentage of vesting of share-based compensation awards.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)				1 Months Ended			12 Months Ended
	Jun. 01, 2017	Jan. 31, 2017	Apr. 29, 2016	May 31, 2018	May 31, 2017	May 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares issued							54,039,554	54,355,535
Common stock reserved for issuance							18,000,000
Vesting period							3 years
Capitalization of share based payment costs							$ 471,000	$ 471,000	$ 471,000
Restricted stock units, weighted average grant date fair value							$ 21.74	$ 13.14	$ 8.52
2014 ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance							2,500,000
Percentage of payroll deduction to compensation							Up to 10%
Percentage of Common Stock through payroll deductions							10.00%
Amount of payroll deduction	$ 22,500,000						$ 21,250,000
Amount of payroll deduction increased							$ 22,500,000
Percentage of closing price of the Common Stock		90.00%					85.00%
Common stock, shares issued							105,672	105,506	139,079
Common stock reserved for issuance							1,926,731
2014 ESPP Plan [Member] \| Offer Terminate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of closing price of the Common Stock		90.00%					85.00%
2014 ESPP Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price							$ 84.11	$ 46.37	$ 31.40
2014 ESPP Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, exercise price							$ 70.61	$ 74.12	$ 35.16
Stock Incentive Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance							14,079,849
Shares available for future grant							18,000,000
Percentage of exercise price fair value option grant in period							100.00%
Number of shares returned for each common stock							2.4
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement							1,260,525
Number of RSUs outstanding							6,694	12,134	17,462
Dividend reinvestment							66	122	187
Restricted stock units, weighted average grant date fair value							$ 111.64
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested							$ 61,626,000	$ 60,302,000	$ 18,844,000
Total compensation expense related to restricted stock unites and stock appreciation rights							$ 19,039,000
Estimated weighted average amortization period							10 months 28 days
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage per year of RSUs from date of grant							33.00%	33.00%	33.00%
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							1 day
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period							13 months
Restricted Stock Units (RSUs) [Member] \| Newport Deferred Compensation [Member] \| Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Newport RSUs converted to MKS RSUs at Merger date							36,599
Newport RSUs converted to MKS RSUs at Merger date and released				5,561	5,515	19,137
RSUs Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description							Employees who are at least 60 years old and have a minimum of 10 Years of Service (as defined in the applicable RSU agreement) are expensed immediately.
Minimum years of service for RSU							10 years
RSUs Granted to Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award vesting period description							Earliest of (1) one day prior to the next annual meeting, (2) 13 months from date of grant, or (3) the effective date of a change in control of the Company.
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options, stock appreciation rights exercised and fair value of RSUs vested							$ 61,626,000	$ 60,302,000	$ 18,844,000
Total compensation expense related to restricted stock unites and stock appreciation rights							$ 19,039,000
Estimated weighted average amortization period							10 months 28 days
Newport [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement			360,674
Newport [Member] \| Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued as per merger agreement			899,851